X-ray tube.



X-RAY TUBE.

Patented Dec 21, 1915.

M INVENTORS H. C. SNOOK & G. H. WHITE.

APPLICATION men NOV. 11. 1911.

WITNESSES m a m m N N g L a N y W W l M as rare FFECE.

HOMER CLYDE SNOOK AND GEORGE HERBERT WHITE, F PHILADELPHIA, PENNSYL- VANIA, ASSIGNORS TO BOENTGEN MANUFACTURING COMPANY, OF PHILADEL- PHIA, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

x-BAY TUBE.

Specification of Letters Patent.

Patented Dec. 2 1, 1915.

Original application filed April 7,- 1911, SerialNo. 619,462. Divided and this application filed November 1 a 17, 1911. Serial No. 660,787;

To all whom it may concern:

Be it known that we, Homnn CLYDE SNOOK' the county of Philadelphia and State of Pennsylvania, haveinvented new and useful Improvements in X-Ray Tubes, of which 'the following is a specification.

Our invention relates to X-ray tubes, and more particularly to the structure thereof.

Our invention resides in improvements in the structure and mode of mounting or supporting the anode or target; resides in the structure of the target or anode; resides in the form of the cathode; and resides in other features hereinafter described and claimed. For an illustration of one of the forms our invention may take, reference is to be had to the accompanying'drawing, in which: Figure l-is a side elevational view of our improved X-ray tube. Fig. 2'is a sectional view on the line 2-2 of Fig. 1. Fig. 3 is a cross sectional view on the line 33 of Fig. 1 through the target or anode.

The X-ray tube comprises the usual glass bulbous portion X, the integral glass tubular stems 1 and 2, and the vacuum regulator 3. At 4 is indicated the glass tip at which the exhausting or pumping is performed and which is sealed off when the proper degree of vacuum within the X-ray tube is v procured.

The target or anode proper is a block or sheet of platinum or other suitable refractory material 5,'secured upon the plug 6 fitting in a hole or bore in the mass 7 of copper or other suitable material. The plug 6 is inserted to such distance that the outer surface of theplate 5-is somewhat below the surface 8 of the member 7. The member 7 has a neck 9 fitting snugly irlto and secured to the copper or other tubular member 10 fitting within the stem 1. This neck 9 may be bored out, as indicated in dotted lines, to make the parts lighter in Weight, if desired. The tubular member 10 is longitudinally slottedat 11 and has a plurality of transverse slots 12 intersecting the longitudinal slot 11. This provides a plurality of independently yielding and resilient members which frictionally engage the inside of the glass neck 1. And the tubular member 10 itself frictionally engages the inside of the neck 1. The slotting as described, insures tube.

that the tubular member 10 shall engage the lnterlor surface of the neck 1 at a plurality of points or over a relativelyextended area, so as to frictionally hold the tube 10 and attached parts in the position shown, and prevent the tube 10 and attached parts from moving under the effects of shocks and other effects, to which the tube may be subjected in shipment or in usage. By this constructlon the pressure per, unit ,area on the interior of the glass stem is not made so great, by our method, to effect the same total friction. Thatis, the strain per unit area in the glass is made low by our method, so that the joining the conductor 13 t0 the terminal 15 p is the platinum or similar wire 16 sealed through the end of the neck 1.

As above stated, the target 5 has its surface sli htly below the surface 8 of the member The edges of the opening around the target '5 operate as a diaphragm to sharply define target 5.

The cathode 17 has the usual concave surface 18 'and'is preferably turned out of a solid block of metal. Into the smaller bore 19 of the cathodel'? extends the conducting rod 20 inclosed in the inner glass stem or tube 21 which extends into the larger bore 22 of the cath de 17. A platinum or other conductor-'23 electrically connects the rod 20 and therefore the cathode 17 with the outer the rays emanating from the terminal 24, the platinum wirebeing sealed.

withinglass in the manner Well understood.

W'e have found that where the external sur-' face of the cathodel'? is parallel or substantially so, even for relatively slight distances, with the inner walls-of the X-ray tube X or the neck 2, there is a bombardment from that surface against the glass of the'tube,

tendin to rupture or weaken the X-ray e have found that this may be preexternal surface of the cathode are at right angles or normal to that surface. And, therefore, by the construction of the cathode substantially as herein described, these emanations where they strike the interior of the stem 2 are spreadout, therefore not sufliciently concentrated to so highly heat the stem locally as to cause its breakage or rupture.

In the regulating neck 3 is disposed a mass 26 of asbestos or other material which will liberate gas to reduce-the vacuum in the X- ray tube X. With this material communicates a conductor sealed through the glass and connecting to the terminal 27. This vacuum regulator is shown upon the part of the bulb X back of the target. By the location of the vacuum regulator upon the bulb proper and not upon one of the tube stems, as, for example, the anode stem 1, when a slotted member 10, as described, is employed for supporting the, target or anode, our arrangement prevents local heating of the inner Walls of the glass stem approximate any of the slots.

This application is a division of our application Serial No. 619,462, filed April 7, 1911, which became Patent No.1,010,197, November 28, 1911.

What we claim is 1. In an X-ray tube, a target member having a front face, a plug inserted in said target member at right angles to said front face thereof, and a target supported on said plug. 7

2. In an X-ray tube, a target member. a plug inserted in said target member at right angles to the faceof said target member, and a target supported on said plug, the face of said target being beneath the face of said target member.

' 3. In combination, a vacuum tube, a tubular neck thereon communicatingwith the interior thereof, a tube engaging in said neck, and an electrode supported by said tube, said' tube having a longitudinal slot extending to the end of said tube remote from said elec trode, said tube having transverse slots between the ends of said longitudinal slot.

4. In combination, a vacuum tube, a tubu lar neck thereon communicating with the interior'thereof, a tube engaging in said neck,

an electrode supported by said tube, said tube having a longitudinal slot extending to the end thereof opposite said electrode, and a plurality of transverse slotsintersecting said longitudinal slot and disposed between the ends of said longitudinal slot.

In testimony whereof We have hereunto aflixed our signatures this 16th day of November, 1911, in the presence of the two subscribing Witnesses.

, HOMER CLYDE SNOOK.

GEORGE HERBERT WHITE. Witnesses A. E. STEINBOCK, ELEANOR T. MoOALL. 

